The present invention relates to Roots-type blowers. Such Roots-type blowers have been used for supercharging internal combustion engines (e.g., Diesel cycle engines, Otto cycle engines, etc.). When used on internal combustion engines, such Roots-type blowers may be a component of a forced induction system that supplies air or an air/fuel mixture to the internal combustion engine. Such forced induction systems supply the internal combustion engine with the air or the air/fuel mixture at a higher pressure than atmospheric pressure. In contrast, naturally aspirated internal combustion engines are supplied with air or an air/fuel mixture at atmospheric pressure. By supplying pressurized air or a pressurized air/fuel mixture to the internal combustion engine, the engine is supercharged. The Roots-type blowers are known as positive displacement superchargers. Positive displacement superchargers substantially deliver a given volume of gas for every revolution of an input shaft at a given pressure and a given temperature. In contrast, certain impeller superchargers are non-positive displacement superchargers. An example Roots-style supercharger is disclosed at U.S. Pat. No. 7,866,966, assigned to the assignee of the present disclosure and incorporated herein by reference in its entirety. Another example Roots-style supercharger is disclosed at U.S. Pat. No. 4,828,467, also assigned to the assignee of the present disclosure and also incorporated herein by reference in its entirety.